Thc conditions which give rise to the necessity for repair of fuel injection pumps are discussed at length in U.S. Pat. No. 4,594,988 and such conditions are equally applicable to this invention. Basically, the necessity arises from the fact that the pumps include a reciprocating piston of a relatively hard material such as steel mounted in a cylinder of a relatively soft material such as aluminum. The fuel injection pump operates at high speed which contributes to wear. Since the accurate and effective operation of these pumps has a very significant effect upon the performance of the engine, it is essential that they be repaired as soon as any significant wear occurs.
The repair method and means disclosed in our U.S. Pat. No. 4,594,988, while effective both for restoring the fuel injection pump's accuracy and efficiency as well as substantially increasing its life, does involve complex machining of the pump housing. This must be carefully done both from the standpoint of accuracy and because the wall thickness remaining after the machining in a significant is critical in a number of cases. Further, because of this such a repair normally can only be done once, there remaining insufficient wall thickness on the pump housing to permit a second machining.